drivers/infiniband/core/addr.c

   1 /*
   2  * Copyright (c) 2005 Voltaire Inc.  All rights reserved.
   3  * Copyright (c) 2002-2005, Network Appliance, Inc. All rights reserved.
   4  * Copyright (c) 1999-2005, Mellanox Technologies, Inc. All rights reserved.
   5  * Copyright (c) 2005 Intel Corporation.  All rights reserved.
   6  *
   7  * This software is available to you under a choice of one of two
   8  * licenses.  You may choose to be licensed under the terms of the GNU
   9  * General Public License (GPL) Version 2, available from the file
  10  * COPYING in the main directory of this source tree, or the
  11  * OpenIB.org BSD license below:
  12  *
  13  *     Redistribution and use in source and binary forms, with or
  14  *     without modification, are permitted provided that the following
  15  *     conditions are met:
  16  *
  17  *      - Redistributions of source code must retain the above
  18  *        copyright notice, this list of conditions and the following
  19  *        disclaimer.
  20  *
  21  *      - Redistributions in binary form must reproduce the above
  22  *        copyright notice, this list of conditions and the following
  23  *        disclaimer in the documentation and/or other materials
  24  *        provided with the distribution.
  25  *
  26  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  27  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  28  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  29  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  30  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  31  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  32  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  33  * SOFTWARE.
  34  */
  35
  36 #include <linux/mutex.h>
  37 #include <linux/inetdevice.h>
  38 #include <linux/slab.h>
  39 #include <linux/workqueue.h>
  40 #include <linux/module.h>
  41 #include <net/arp.h>
  42 #include <net/neighbour.h>
  43 #include <net/route.h>
  44 #include <net/netevent.h>
  45 #include <net/ipv6_stubs.h>
  46 #include <net/ip6_route.h>
  47 #include <rdma/ib_addr.h>
  48 #include <rdma/ib_cache.h>
  49 #include <rdma/ib_sa.h>
  50 #include <rdma/ib.h>
  51 #include <rdma/rdma_netlink.h>
  52 #include <net/netlink.h>
  53
  54 #include "core_priv.h"
  55
  56 struct addr_req {
  57         struct list_head list;
  58         struct sockaddr_storage src_addr;
  59         struct sockaddr_storage dst_addr;
  60         struct rdma_dev_addr *addr;
  61         void *context;
  62         void (*callback)(int status, struct sockaddr *src_addr,
  63                          struct rdma_dev_addr *addr, void *context);
  64         unsigned long timeout;
  65         struct delayed_work work;
  66         bool resolve_by_gid_attr;       /* Consider gid attr in resolve phase */
  67         int status;
  68         u32 seq;
  69 };
  70
  71 static atomic_t ib_nl_addr_request_seq = ATOMIC_INIT(0);
  72
  73 static DEFINE_SPINLOCK(lock);
  74 static LIST_HEAD(req_list);
  75 static struct workqueue_struct *addr_wq;
  76
  77 static const struct nla_policy ib_nl_addr_policy[LS_NLA_TYPE_MAX] = {
  78         [LS_NLA_TYPE_DGID] = {.type = NLA_BINARY,
  79                 .len = sizeof(struct rdma_nla_ls_gid),
  80                 .validation_type = NLA_VALIDATE_MIN,
  81                 .min = sizeof(struct rdma_nla_ls_gid)},
  82 };
  83
  84 static inline bool ib_nl_is_good_ip_resp(const struct nlmsghdr *nlh)
  85 {
  86         struct nlattr *tb[LS_NLA_TYPE_MAX] = {};
  87         int ret;
  88
  89         if (nlh->nlmsg_flags & RDMA_NL_LS_F_ERR)
  90                 return false;
  91
  92         ret = nla_parse_deprecated(tb, LS_NLA_TYPE_MAX - 1, nlmsg_data(nlh),
  93                                    nlmsg_len(nlh), ib_nl_addr_policy, NULL);
  94         if (ret)
  95                 return false;
  96
  97         return true;
  98 }
  99
 100 static void ib_nl_process_good_ip_rsep(const struct nlmsghdr *nlh)
 101 {
 102         const struct nlattr *head, *curr;
 103         union ib_gid gid;
 104         struct addr_req *req;
 105         int len, rem;
 106         int found = 0;
 107
 108         head = (const struct nlattr *)nlmsg_data(nlh);
 109         len = nlmsg_len(nlh);
 110
 111         nla_for_each_attr(curr, head, len, rem) {
 112                 if (curr->nla_type == LS_NLA_TYPE_DGID)
 113                         memcpy(&gid, nla_data(curr), nla_len(curr));
 114         }
 115
 116         spin_lock_bh(&lock);
 117         list_for_each_entry(req, &req_list, list) {
 118                 if (nlh->nlmsg_seq != req->seq)
 119                         continue;
 120                 /* We set the DGID part, the rest was set earlier */
 121                 rdma_addr_set_dgid(req->addr, &gid);
 122                 req->status = 0;
 123                 found = 1;
 124                 break;
 125         }
 126         spin_unlock_bh(&lock);
 127
 128         if (!found)
 129                 pr_info("Couldn't find request waiting for DGID: %pI6\n",
 130                         &gid);
 131 }
 132
 133 int ib_nl_handle_ip_res_resp(struct sk_buff *skb,
 134                              struct nlmsghdr *nlh,
 135                              struct netlink_ext_ack *extack)
 136 {
 137         if ((nlh->nlmsg_flags & NLM_F_REQUEST) ||
 138             !(NETLINK_CB(skb).sk))
 139                 return -EPERM;
 140
 141         if (ib_nl_is_good_ip_resp(nlh))
 142                 ib_nl_process_good_ip_rsep(nlh);
 143
 144         return 0;
 145 }
 146
 147 static int ib_nl_ip_send_msg(struct rdma_dev_addr *dev_addr,
 148                              const void *daddr,
 149                              u32 seq, u16 family)
 150 {
 151         struct sk_buff *skb = NULL;
 152         struct nlmsghdr *nlh;
 153         struct rdma_ls_ip_resolve_header *header;
 154         void *data;
 155         size_t size;
 156         int attrtype;
 157         int len;
 158
 159         if (family == AF_INET) {
 160                 size = sizeof(struct in_addr);
 161                 attrtype = RDMA_NLA_F_MANDATORY | LS_NLA_TYPE_IPV4;
 162         } else {
 163                 size = sizeof(struct in6_addr);
 164                 attrtype = RDMA_NLA_F_MANDATORY | LS_NLA_TYPE_IPV6;
 165         }
 166
 167         len = nla_total_size(sizeof(size));
 168         len += NLMSG_ALIGN(sizeof(*header));
 169
 170         skb = nlmsg_new(len, GFP_KERNEL);
 171         if (!skb)
 172                 return -ENOMEM;
 173
 174         data = ibnl_put_msg(skb, &nlh, seq, 0, RDMA_NL_LS,
 175                             RDMA_NL_LS_OP_IP_RESOLVE, NLM_F_REQUEST);
 176         if (!data) {
 177                 nlmsg_free(skb);
 178                 return -ENODATA;
 179         }
 180
 181         /* Construct the family header first */
 182         header = skb_put(skb, NLMSG_ALIGN(sizeof(*header)));
 183         header->ifindex = dev_addr->bound_dev_if;
 184         nla_put(skb, attrtype, size, daddr);
 185
 186         /* Repair the nlmsg header length */
 187         nlmsg_end(skb, nlh);
 188         rdma_nl_multicast(&init_net, skb, RDMA_NL_GROUP_LS, GFP_KERNEL);
 189
 190         /* Make the request retry, so when we get the response from userspace
 191          * we will have something.
 192          */
 193         return -ENODATA;
 194 }
 195
 196 int rdma_addr_size(const struct sockaddr *addr)
 197 {
 198         switch (addr->sa_family) {
 199         case AF_INET:
 200                 return sizeof(struct sockaddr_in);
 201         case AF_INET6:
 202                 return sizeof(struct sockaddr_in6);
 203         case AF_IB:
 204                 return sizeof(struct sockaddr_ib);
 205         default:
 206                 return 0;
 207         }
 208 }
 209 EXPORT_SYMBOL(rdma_addr_size);
 210
 211 int rdma_addr_size_in6(struct sockaddr_in6 *addr)
 212 {
 213         int ret = rdma_addr_size((struct sockaddr *) addr);
 214
 215         return ret <= sizeof(*addr) ? ret : 0;
 216 }
 217 EXPORT_SYMBOL(rdma_addr_size_in6);
 218
 219 int rdma_addr_size_kss(struct __kernel_sockaddr_storage *addr)
 220 {
 221         int ret = rdma_addr_size((struct sockaddr *) addr);
 222
 223         return ret <= sizeof(*addr) ? ret : 0;
 224 }
 225 EXPORT_SYMBOL(rdma_addr_size_kss);
 226
 227 /**
 228  * rdma_copy_src_l2_addr - Copy netdevice source addresses
 229  * @dev_addr:   Destination address pointer where to copy the addresses
 230  * @dev:        Netdevice whose source addresses to copy
 231  *
 232  * rdma_copy_src_l2_addr() copies source addresses from the specified netdevice.
 233  * This includes unicast address, broadcast address, device type and
 234  * interface index.
 235  */
 236 void rdma_copy_src_l2_addr(struct rdma_dev_addr *dev_addr,
 237                            const struct net_device *dev)
 238 {
 239         dev_addr->dev_type = dev->type;
 240         memcpy(dev_addr->src_dev_addr, dev->dev_addr, MAX_ADDR_LEN);
 241         memcpy(dev_addr->broadcast, dev->broadcast, MAX_ADDR_LEN);
 242         dev_addr->bound_dev_if = dev->ifindex;
 243 }
 244 EXPORT_SYMBOL(rdma_copy_src_l2_addr);
 245
 246 static struct net_device *
 247 rdma_find_ndev_for_src_ip_rcu(struct net *net, const struct sockaddr *src_in)
 248 {
 249         struct net_device *dev = NULL;
 250         int ret = -EADDRNOTAVAIL;
 251
 252         switch (src_in->sa_family) {
 253         case AF_INET:
 254                 dev = __ip_dev_find(net,
 255                                     ((const struct sockaddr_in *)src_in)->sin_addr.s_addr,
 256                                     false);
 257                 if (dev)
 258                         ret = 0;
 259                 break;
 260 #if IS_ENABLED(CONFIG_IPV6)
 261         case AF_INET6:
 262                 for_each_netdev_rcu(net, dev) {
 263                         if (ipv6_chk_addr(net,
 264                                           &((const struct sockaddr_in6 *)src_in)->sin6_addr,
 265                                           dev, 1)) {
 266                                 ret = 0;
 267                                 break;
 268                         }
 269                 }
 270                 break;
 271 #endif
 272         }
 273         return ret ? ERR_PTR(ret) : dev;
 274 }
 275
 276 int rdma_translate_ip(const struct sockaddr *addr,
 277                       struct rdma_dev_addr *dev_addr)
 278 {
 279         struct net_device *dev;
 280
 281         if (dev_addr->bound_dev_if) {
 282                 dev = dev_get_by_index(dev_addr->net, dev_addr->bound_dev_if);
 283                 if (!dev)
 284                         return -ENODEV;
 285                 rdma_copy_src_l2_addr(dev_addr, dev);
 286                 dev_put(dev);
 287                 return 0;
 288         }
 289
 290         rcu_read_lock();
 291         dev = rdma_find_ndev_for_src_ip_rcu(dev_addr->net, addr);
 292         if (!IS_ERR(dev))
 293                 rdma_copy_src_l2_addr(dev_addr, dev);
 294         rcu_read_unlock();
 295         return PTR_ERR_OR_ZERO(dev);
 296 }
 297 EXPORT_SYMBOL(rdma_translate_ip);
 298
 299 static void set_timeout(struct addr_req *req, unsigned long time)
 300 {
 301         unsigned long delay;
 302
 303         delay = time - jiffies;
 304         if ((long)delay < 0)
 305                 delay = 0;
 306
 307         mod_delayed_work(addr_wq, &req->work, delay);
 308 }
 309
 310 static void queue_req(struct addr_req *req)
 311 {
 312         spin_lock_bh(&lock);
 313         list_add_tail(&req->list, &req_list);
 314         set_timeout(req, req->timeout);
 315         spin_unlock_bh(&lock);
 316 }
 317
 318 static int ib_nl_fetch_ha(struct rdma_dev_addr *dev_addr,
 319                           const void *daddr, u32 seq, u16 family)
 320 {
 321         if (!rdma_nl_chk_listeners(RDMA_NL_GROUP_LS))
 322                 return -EADDRNOTAVAIL;
 323
 324         return ib_nl_ip_send_msg(dev_addr, daddr, seq, family);
 325 }
 326
 327 static int dst_fetch_ha(const struct dst_entry *dst,
 328                         struct rdma_dev_addr *dev_addr,
 329                         const void *daddr)
 330 {
 331         struct neighbour *n;
 332         int ret = 0;
 333
 334         n = dst_neigh_lookup(dst, daddr);
 335         if (!n)
 336                 return -ENODATA;
 337
 338         if (!(n->nud_state & NUD_VALID)) {
 339                 neigh_event_send(n, NULL);
 340                 ret = -ENODATA;
 341         } else {
 342                 neigh_ha_snapshot(dev_addr->dst_dev_addr, n, dst->dev);
 343         }
 344
 345         neigh_release(n);
 346
 347         return ret;
 348 }
 349
 350 static bool has_gateway(const struct dst_entry *dst, sa_family_t family)
 351 {
 352         struct rtable *rt;
 353         struct rt6_info *rt6;
 354
 355         if (family == AF_INET) {
 356                 rt = container_of(dst, struct rtable, dst);
 357                 return rt->rt_uses_gateway;
 358         }
 359
 360         rt6 = container_of(dst, struct rt6_info, dst);
 361         return rt6->rt6i_flags & RTF_GATEWAY;
 362 }
 363
 364 static int fetch_ha(const struct dst_entry *dst, struct rdma_dev_addr *dev_addr,
 365                     const struct sockaddr *dst_in, u32 seq)
 366 {
 367         const struct sockaddr_in *dst_in4 =
 368                 (const struct sockaddr_in *)dst_in;
 369         const struct sockaddr_in6 *dst_in6 =
 370                 (const struct sockaddr_in6 *)dst_in;
 371         const void *daddr = (dst_in->sa_family == AF_INET) ?
 372                 (const void *)&dst_in4->sin_addr.s_addr :
 373                 (const void *)&dst_in6->sin6_addr;
 374         sa_family_t family = dst_in->sa_family;
 375
 376         might_sleep();
 377
 378         /* If we have a gateway in IB mode then it must be an IB network */
 379         if (has_gateway(dst, family) && dev_addr->network == RDMA_NETWORK_IB)
 380                 return ib_nl_fetch_ha(dev_addr, daddr, seq, family);
 381         else
 382                 return dst_fetch_ha(dst, dev_addr, daddr);
 383 }
 384
 385 static int addr4_resolve(struct sockaddr *src_sock,
 386                          const struct sockaddr *dst_sock,
 387                          struct rdma_dev_addr *addr,
 388                          struct rtable **prt)
 389 {
 390         struct sockaddr_in *src_in = (struct sockaddr_in *)src_sock;
 391         const struct sockaddr_in *dst_in =
 392                         (const struct sockaddr_in *)dst_sock;
 393
 394         __be32 src_ip = src_in->sin_addr.s_addr;
 395         __be32 dst_ip = dst_in->sin_addr.s_addr;
 396         struct rtable *rt;
 397         struct flowi4 fl4;
 398         int ret;
 399
 400         memset(&fl4, 0, sizeof(fl4));
 401         fl4.daddr = dst_ip;
 402         fl4.saddr = src_ip;
 403         fl4.flowi4_oif = addr->bound_dev_if;
 404         rt = ip_route_output_key(addr->net, &fl4);
 405         ret = PTR_ERR_OR_ZERO(rt);
 406         if (ret)
 407                 return ret;
 408
 409         src_in->sin_addr.s_addr = fl4.saddr;
 410
 411         addr->hoplimit = ip4_dst_hoplimit(&rt->dst);
 412
 413         *prt = rt;
 414         return 0;
 415 }
 416
 417 #if IS_ENABLED(CONFIG_IPV6)
 418 static int addr6_resolve(struct sockaddr *src_sock,
 419                          const struct sockaddr *dst_sock,
 420                          struct rdma_dev_addr *addr,
 421                          struct dst_entry **pdst)
 422 {
 423         struct sockaddr_in6 *src_in = (struct sockaddr_in6 *)src_sock;
 424         const struct sockaddr_in6 *dst_in =
 425                                 (const struct sockaddr_in6 *)dst_sock;
 426         struct flowi6 fl6;
 427         struct dst_entry *dst;
 428
 429         memset(&fl6, 0, sizeof fl6);
 430         fl6.daddr = dst_in->sin6_addr;
 431         fl6.saddr = src_in->sin6_addr;
 432         fl6.flowi6_oif = addr->bound_dev_if;
 433
 434         dst = ipv6_stub->ipv6_dst_lookup_flow(addr->net, NULL, &fl6, NULL);
 435         if (IS_ERR(dst))
 436                 return PTR_ERR(dst);
 437
 438         if (ipv6_addr_any(&src_in->sin6_addr))
 439                 src_in->sin6_addr = fl6.saddr;
 440
 441         addr->hoplimit = ip6_dst_hoplimit(dst);
 442
 443         *pdst = dst;
 444         return 0;
 445 }
 446 #else
 447 static int addr6_resolve(struct sockaddr *src_sock,
 448                          const struct sockaddr *dst_sock,
 449                          struct rdma_dev_addr *addr,
 450                          struct dst_entry **pdst)
 451 {
 452         return -EADDRNOTAVAIL;
 453 }
 454 #endif
 455
 456 static int addr_resolve_neigh(const struct dst_entry *dst,
 457                               const struct sockaddr *dst_in,
 458                               struct rdma_dev_addr *addr,
 459                               unsigned int ndev_flags,
 460                               u32 seq)
 461 {
 462         int ret = 0;
 463
 464         if (ndev_flags & IFF_LOOPBACK) {
 465                 memcpy(addr->dst_dev_addr, addr->src_dev_addr, MAX_ADDR_LEN);
 466         } else {
 467                 if (!(ndev_flags & IFF_NOARP)) {
 468                         /* If the device doesn't do ARP internally */
 469                         ret = fetch_ha(dst, addr, dst_in, seq);
 470                 }
 471         }
 472         return ret;
 473 }
 474
 475 static int copy_src_l2_addr(struct rdma_dev_addr *dev_addr,
 476                             const struct sockaddr *dst_in,
 477                             const struct dst_entry *dst,
 478                             const struct net_device *ndev)
 479 {
 480         int ret = 0;
 481
 482         if (dst->dev->flags & IFF_LOOPBACK)
 483                 ret = rdma_translate_ip(dst_in, dev_addr);
 484         else
 485                 rdma_copy_src_l2_addr(dev_addr, dst->dev);
 486
 487         /*
 488          * If there's a gateway and type of device not ARPHRD_INFINIBAND,
 489          * we're definitely in RoCE v2 (as RoCE v1 isn't routable) set the
 490          * network type accordingly.
 491          */
 492         if (has_gateway(dst, dst_in->sa_family) &&
 493             ndev->type != ARPHRD_INFINIBAND)
 494                 dev_addr->network = dst_in->sa_family == AF_INET ?
 495                                                 RDMA_NETWORK_IPV4 :
 496                                                 RDMA_NETWORK_IPV6;
 497         else
 498                 dev_addr->network = RDMA_NETWORK_IB;
 499
 500         return ret;
 501 }
 502
 503 static int rdma_set_src_addr_rcu(struct rdma_dev_addr *dev_addr,
 504                                  unsigned int *ndev_flags,
 505                                  const struct sockaddr *dst_in,
 506                                  const struct dst_entry *dst)
 507 {
 508         struct net_device *ndev = READ_ONCE(dst->dev);
 509
 510         *ndev_flags = ndev->flags;
 511         /* A physical device must be the RDMA device to use */
 512         if (ndev->flags & IFF_LOOPBACK) {
 513                 /*
 514                  * RDMA (IB/RoCE, iWarp) doesn't run on lo interface or
 515                  * loopback IP address. So if route is resolved to loopback
 516                  * interface, translate that to a real ndev based on non
 517                  * loopback IP address.
 518                  */
 519                 ndev = rdma_find_ndev_for_src_ip_rcu(dev_net(ndev), dst_in);
 520                 if (IS_ERR(ndev))
 521                         return -ENODEV;
 522         }
 523
 524         return copy_src_l2_addr(dev_addr, dst_in, dst, ndev);
 525 }
 526
 527 static int set_addr_netns_by_gid_rcu(struct rdma_dev_addr *addr)
 528 {
 529         struct net_device *ndev;
 530
 531         ndev = rdma_read_gid_attr_ndev_rcu(addr->sgid_attr);
 532         if (IS_ERR(ndev))
 533                 return PTR_ERR(ndev);
 534
 535         /*
 536          * Since we are holding the rcu, reading net and ifindex
 537          * are safe without any additional reference; because
 538          * change_net_namespace() in net/core/dev.c does rcu sync
 539          * after it changes the state to IFF_DOWN and before
 540          * updating netdev fields {net, ifindex}.
 541          */
 542         addr->net = dev_net(ndev);
 543         addr->bound_dev_if = ndev->ifindex;
 544         return 0;
 545 }
 546
 547 static void rdma_addr_set_net_defaults(struct rdma_dev_addr *addr)
 548 {
 549         addr->net = &init_net;
 550         addr->bound_dev_if = 0;
 551 }
 552
 553 static int addr_resolve(struct sockaddr *src_in,
 554                         const struct sockaddr *dst_in,
 555                         struct rdma_dev_addr *addr,
 556                         bool resolve_neigh,
 557                         bool resolve_by_gid_attr,
 558                         u32 seq)
 559 {
 560         struct dst_entry *dst = NULL;
 561         unsigned int ndev_flags = 0;
 562         struct rtable *rt = NULL;
 563         int ret;
 564
 565         if (!addr->net) {
 566                 pr_warn_ratelimited("%s: missing namespace\n", __func__);
 567                 return -EINVAL;
 568         }
 569
 570         rcu_read_lock();
 571         if (resolve_by_gid_attr) {
 572                 if (!addr->sgid_attr) {
 573                         rcu_read_unlock();
 574                         pr_warn_ratelimited("%s: missing gid_attr\n", __func__);
 575                         return -EINVAL;
 576                 }
 577                 /*
 578                  * If the request is for a specific gid attribute of the
 579                  * rdma_dev_addr, derive net from the netdevice of the
 580                  * GID attribute.
 581                  */
 582                 ret = set_addr_netns_by_gid_rcu(addr);
 583                 if (ret) {
 584                         rcu_read_unlock();
 585                         return ret;
 586                 }
 587         }
 588         if (src_in->sa_family == AF_INET) {
 589                 ret = addr4_resolve(src_in, dst_in, addr, &rt);
 590                 dst = &rt->dst;
 591         } else {
 592                 ret = addr6_resolve(src_in, dst_in, addr, &dst);
 593         }
 594         if (ret) {
 595                 rcu_read_unlock();
 596                 goto done;
 597         }
 598         ret = rdma_set_src_addr_rcu(addr, &ndev_flags, dst_in, dst);
 599         rcu_read_unlock();
 600
 601         /*
 602          * Resolve neighbor destination address if requested and
 603          * only if src addr translation didn't fail.
 604          */
 605         if (!ret && resolve_neigh)
 606                 ret = addr_resolve_neigh(dst, dst_in, addr, ndev_flags, seq);
 607
 608         if (src_in->sa_family == AF_INET)
 609                 ip_rt_put(rt);
 610         else
 611                 dst_release(dst);
 612 done:
 613         /*
 614          * Clear the addr net to go back to its original state, only if it was
 615          * derived from GID attribute in this context.
 616          */
 617         if (resolve_by_gid_attr)
 618                 rdma_addr_set_net_defaults(addr);
 619         return ret;
 620 }
 621
 622 static void process_one_req(struct work_struct *_work)
 623 {
 624         struct addr_req *req;
 625         struct sockaddr *src_in, *dst_in;
 626
 627         req = container_of(_work, struct addr_req, work.work);
 628
 629         if (req->status == -ENODATA) {
 630                 src_in = (struct sockaddr *)&req->src_addr;
 631                 dst_in = (struct sockaddr *)&req->dst_addr;
 632                 req->status = addr_resolve(src_in, dst_in, req->addr,
 633                                            true, req->resolve_by_gid_attr,
 634                                            req->seq);
 635                 if (req->status && time_after_eq(jiffies, req->timeout)) {
 636                         req->status = -ETIMEDOUT;
 637                 } else if (req->status == -ENODATA) {
 638                         /* requeue the work for retrying again */
 639                         spin_lock_bh(&lock);
 640                         if (!list_empty(&req->list))
 641                                 set_timeout(req, req->timeout);
 642                         spin_unlock_bh(&lock);
 643                         return;
 644                 }
 645         }
 646
 647         req->callback(req->status, (struct sockaddr *)&req->src_addr,
 648                 req->addr, req->context);
 649         req->callback = NULL;
 650
 651         spin_lock_bh(&lock);
 652         /*
 653          * Although the work will normally have been canceled by the workqueue,
 654          * it can still be requeued as long as it is on the req_list.
 655          */
 656         cancel_delayed_work(&req->work);
 657         if (!list_empty(&req->list)) {
 658                 list_del_init(&req->list);
 659                 kfree(req);
 660         }
 661         spin_unlock_bh(&lock);
 662 }
 663
 664 int rdma_resolve_ip(struct sockaddr *src_addr, const struct sockaddr *dst_addr,
 665                     struct rdma_dev_addr *addr, unsigned long timeout_ms,
 666                     void (*callback)(int status, struct sockaddr *src_addr,
 667                                      struct rdma_dev_addr *addr, void *context),
 668                     bool resolve_by_gid_attr, void *context)
 669 {
 670         struct sockaddr *src_in, *dst_in;
 671         struct addr_req *req;
 672         int ret = 0;
 673
 674         req = kzalloc(sizeof *req, GFP_KERNEL);
 675         if (!req)
 676                 return -ENOMEM;
 677
 678         src_in = (struct sockaddr *) &req->src_addr;
 679         dst_in = (struct sockaddr *) &req->dst_addr;
 680
 681         if (src_addr) {
 682                 if (src_addr->sa_family != dst_addr->sa_family) {
 683                         ret = -EINVAL;
 684                         goto err;
 685                 }
 686
 687                 memcpy(src_in, src_addr, rdma_addr_size(src_addr));
 688         } else {
 689                 src_in->sa_family = dst_addr->sa_family;
 690         }
 691
 692         memcpy(dst_in, dst_addr, rdma_addr_size(dst_addr));
 693         req->addr = addr;
 694         req->callback = callback;
 695         req->context = context;
 696         req->resolve_by_gid_attr = resolve_by_gid_attr;
 697         INIT_DELAYED_WORK(&req->work, process_one_req);
 698         req->seq = (u32)atomic_inc_return(&ib_nl_addr_request_seq);
 699
 700         req->status = addr_resolve(src_in, dst_in, addr, true,
 701                                    req->resolve_by_gid_attr, req->seq);
 702         switch (req->status) {
 703         case 0:
 704                 req->timeout = jiffies;
 705                 queue_req(req);
 706                 break;
 707         case -ENODATA:
 708                 req->timeout = msecs_to_jiffies(timeout_ms) + jiffies;
 709                 queue_req(req);
 710                 break;
 711         default:
 712                 ret = req->status;
 713                 goto err;
 714         }
 715         return ret;
 716 err:
 717         kfree(req);
 718         return ret;
 719 }
 720 EXPORT_SYMBOL(rdma_resolve_ip);
 721
 722 int roce_resolve_route_from_path(struct sa_path_rec *rec,
 723                                  const struct ib_gid_attr *attr)
 724 {
 725         union {
 726                 struct sockaddr     _sockaddr;
 727                 struct sockaddr_in  _sockaddr_in;
 728                 struct sockaddr_in6 _sockaddr_in6;
 729         } sgid, dgid;
 730         struct rdma_dev_addr dev_addr = {};
 731         int ret;
 732
 733         might_sleep();
 734
 735         if (rec->roce.route_resolved)
 736                 return 0;
 737
 738         rdma_gid2ip((struct sockaddr *)&sgid, &rec->sgid);
 739         rdma_gid2ip((struct sockaddr *)&dgid, &rec->dgid);
 740
 741         if (sgid._sockaddr.sa_family != dgid._sockaddr.sa_family)
 742                 return -EINVAL;
 743
 744         if (!attr || !attr->ndev)
 745                 return -EINVAL;
 746
 747         dev_addr.net = &init_net;
 748         dev_addr.sgid_attr = attr;
 749
 750         ret = addr_resolve((struct sockaddr *)&sgid, (struct sockaddr *)&dgid,
 751                            &dev_addr, false, true, 0);
 752         if (ret)
 753                 return ret;
 754
 755         if ((dev_addr.network == RDMA_NETWORK_IPV4 ||
 756              dev_addr.network == RDMA_NETWORK_IPV6) &&
 757             rec->rec_type != SA_PATH_REC_TYPE_ROCE_V2)
 758                 return -EINVAL;
 759
 760         rec->roce.route_resolved = true;
 761         return 0;
 762 }
 763
 764 /**
 765  * rdma_addr_cancel - Cancel resolve ip request
 766  * @addr:       Pointer to address structure given previously
 767  *              during rdma_resolve_ip().
 768  * rdma_addr_cancel() is synchronous function which cancels any pending
 769  * request if there is any.
 770  */
 771 void rdma_addr_cancel(struct rdma_dev_addr *addr)
 772 {
 773         struct addr_req *req, *temp_req;
 774         struct addr_req *found = NULL;
 775
 776         spin_lock_bh(&lock);
 777         list_for_each_entry_safe(req, temp_req, &req_list, list) {
 778                 if (req->addr == addr) {
 779                         /*
 780                          * Removing from the list means we take ownership of
 781                          * the req
 782                          */
 783                         list_del_init(&req->list);
 784                         found = req;
 785                         break;
 786                 }
 787         }
 788         spin_unlock_bh(&lock);
 789
 790         if (!found)
 791                 return;
 792
 793         /*
 794          * sync canceling the work after removing it from the req_list
 795          * guarentees no work is running and none will be started.
 796          */
 797         cancel_delayed_work_sync(&found->work);
 798         kfree(found);
 799 }
 800 EXPORT_SYMBOL(rdma_addr_cancel);
 801
 802 struct resolve_cb_context {
 803         struct completion comp;
 804         int status;
 805 };
 806
 807 static void resolve_cb(int status, struct sockaddr *src_addr,
 808              struct rdma_dev_addr *addr, void *context)
 809 {
 810         ((struct resolve_cb_context *)context)->status = status;
 811         complete(&((struct resolve_cb_context *)context)->comp);
 812 }
 813
 814 int rdma_addr_find_l2_eth_by_grh(const union ib_gid *sgid,
 815                                  const union ib_gid *dgid,
 816                                  u8 *dmac, const struct ib_gid_attr *sgid_attr,
 817                                  int *hoplimit)
 818 {
 819         struct rdma_dev_addr dev_addr;
 820         struct resolve_cb_context ctx;
 821         union {
 822                 struct sockaddr_in  _sockaddr_in;
 823                 struct sockaddr_in6 _sockaddr_in6;
 824         } sgid_addr, dgid_addr;
 825         int ret;
 826
 827         rdma_gid2ip((struct sockaddr *)&sgid_addr, sgid);
 828         rdma_gid2ip((struct sockaddr *)&dgid_addr, dgid);
 829
 830         memset(&dev_addr, 0, sizeof(dev_addr));
 831         dev_addr.net = &init_net;
 832         dev_addr.sgid_attr = sgid_attr;
 833
 834         init_completion(&ctx.comp);
 835         ret = rdma_resolve_ip((struct sockaddr *)&sgid_addr,
 836                               (struct sockaddr *)&dgid_addr, &dev_addr, 1000,
 837                               resolve_cb, true, &ctx);
 838         if (ret)
 839                 return ret;
 840
 841         wait_for_completion(&ctx.comp);
 842
 843         ret = ctx.status;
 844         if (ret)
 845                 return ret;
 846
 847         memcpy(dmac, dev_addr.dst_dev_addr, ETH_ALEN);
 848         *hoplimit = dev_addr.hoplimit;
 849         return 0;
 850 }
 851
 852 static int netevent_callback(struct notifier_block *self, unsigned long event,
 853         void *ctx)
 854 {
 855         struct addr_req *req;
 856
 857         if (event == NETEVENT_NEIGH_UPDATE) {
 858                 struct neighbour *neigh = ctx;
 859
 860                 if (neigh->nud_state & NUD_VALID) {
 861                         spin_lock_bh(&lock);
 862                         list_for_each_entry(req, &req_list, list)
 863                                 set_timeout(req, jiffies);
 864                         spin_unlock_bh(&lock);
 865                 }
 866         }
 867         return 0;
 868 }
 869
 870 static struct notifier_block nb = {
 871         .notifier_call = netevent_callback
 872 };
 873
 874 int addr_init(void)
 875 {
 876         addr_wq = alloc_ordered_workqueue("ib_addr", 0);
 877         if (!addr_wq)
 878                 return -ENOMEM;
 879
 880         register_netevent_notifier(&nb);
 881
 882         return 0;
 883 }
 884
 885 void addr_cleanup(void)
 886 {
 887         unregister_netevent_notifier(&nb);
 888         destroy_workqueue(addr_wq);
 889         WARN_ON(!list_empty(&req_list));
 890 }